J. Andrew Foster
The Athenian “Grain Tax Law” of 374/3 BCE regulates those who seek to collect the in kind 1/12th (8.33%) tax upon the annual wheat and barley production on Lemnos, Imbros and Skyros (Stroud 1998). The law’s author, Agyrrhios, permits individuals (ὁ πρίαμενος) and syndicates (συμμορία), composed of precisely six members, to bid. Individual buyers must agree to supply at least one portion (μερίς) comprised of 500 medimnoi of grain at the ratio of 1: 4, wheat to barley. Symmories contract for a minimum of six merides. Individuals must provide two sureties per meris contracted. The Council must approve of the men pledging surety. A symmory is not required to provide sureties external to the syndicate, but members are held jointly liable:
ἡ πόλις πράξει τὴν συμμορ[ία]-
ν τὸν σῖτον κ‹α›ὶ παρ ̓ἑνὸς καὶ παρ ̓ ἁπάν[τω]-
ν τῶν ἐν τῆι συμμορίαι ὄντων, ἕως ἂ̣ν τ[ὰ α]-
The City will collect the grain from one and from all of the members in the symmory until it [the City] receives its quota.
(33-6. Cf. [Dem.] 56.45 [Harris 1989, 341])
In addition to prescribing joint liability, Agyrrhios’ law does not require that any particular symmorist supply a specific amount of grain. The law only dictates that the symmory must meet its quota.
The significance of Agyrrhios’ rules governing symmories has not been fully appreciated. Stroud rightly observed that, qua symmory, a group could create a more “vertically integrated” operation (Stroud 1998, 65. Cf. Moreno 2003, 101). I show that Argyrrhios’ distinctive regulations mandating joint liability and permitting “asset pooling” not only permits greater specialization, but strongly incentivizes bidders to form a symmory composed of a more heterogeneous group of individuals who possess a broader cross section of knowledge, experience, skills, and endowments. For example, a Lemnian cleruch who is intimately familiar with local agrarian conditions, but cannot contribute a meris of grain, provides an “information surplus” in lieu of grain. Given greater freedom to select uniquely endowed partners, a symmory enjoys a significant comparative advantage when bidding for and subsequently fulfilling the concession.
Second, joint liability ensures more rigorous selection of individual symmorists and better oversight of the group. Each member is assigned a full share of risk: any deficiency in any aspect of the purchase of the concession, collection, transport and deposit of the grain prospectively harms each and every syndicate member regardless of their role in the enterprise. By distinguishing liability from individual performance (Wolff 1941, 418), the law strongly incentivizes prospective partners to vet each other stringently. Rigorous self-selection is matched by careful self-monitoring throughout the entire process (Mora 2010, 21-23). In contrast, the Council members do not have a similar stake in the viability of an individual buyer’s surety, who, like Meixidemos of Myrrhinous, may not be reliable (SEG 12.100; Osborne 1985, 45).
Self-selection, joint liability, and self-monitoring are the essential characteristics of Agyrrhios’ symmories. Agyrrhios’ strictures are closely analogous to the rules that micro-credit institutions such as Grameen Bank. Grameen extends loans to groups of borrowers who individually present too great a credit risk (Banerjee and Duflo, 2011, 166-7). Grameen requires that borrowers form groups and that group members be jointly liable for repayment. In response to these rules, groups carefully self-select membership and rigorously self-monitor for compliance (Chowdhury, 2010, 68-70). Grameen reports higher repayment rates than traditional credit arrangements (Morduch, 1999, 1575). Agyrrhios’ law employs strikingly similar methods to overcome the compliance problems intrinsic to enlisting credit constrained agents to collect a time-sensitive, in-kind tax from a distance. Argyrrhios’ ingenious, “micro-finance” regime led potential concessionaires to form symmories that more efficiently and more reliably supplied grain “for the people” (ὅπως ἂν τῶι δήμωι σῖ[το]ς ἦι [5-6]).